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determine the angles of an arc only by the axis and paramter range

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Sebastian Hoogen 2014-12-19 14:35:38 +01:00 committed by wmayer
parent 5ecf5b2ef6
commit 099ece5c00
1 changed files with 8 additions and 63 deletions
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71
src/Mod/Draft/importDXF.py
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@ -1353,46 +1353,12 @@ def getArcData(edge):
# closed circle
return DraftVecUtils.tup(ce), radius, 0, 0
else:
# method 1 - find direction of arc from tangents - not reliable
#tang1 = edge.Curve.tangent(edge.ParameterRange[0])
#tang2 = edge.Curve.tangent(edge.ParameterRange[1])
# following code doesn't seem to give right result?
# cross1 = Vector.cross(Vector(tang1[0][0],tang1[0][1],tang1[0][2]),Vector(tang2[0][0],tang2[0][1],tang2[0][2]))
# if cross1[2] > 0: # >0 ccw <0 cw
# ve1 = edge.Vertexes[0].Point
# ve2 = edge.Vertexes[-1].Point
# else:
# ve1 = edge.Vertexes[-1].Point
# ve2 = edge.Vertexes[0].Point
# method 3 - recreate an arc and check if the length is the same
ve1 = edge.Vertexes[0].Point
ve2 = edge.Vertexes[-1].Point
ang1 = -math.degrees(DraftVecUtils.angle(ve1.sub(ce)))
ang2 = -math.degrees(DraftVecUtils.angle(ve2.sub(ce)))
if round(ang1,Draft.precision()) == round(ang2,Draft.precision()):
return None,None, None, None
if edge.Curve.Axis.z < 0.0:
ang1, ang2 = ang2, ang1
pseudoarc = Part.ArcOfCircle(edge.Curve,math.radians(ang1),math.radians(ang2)).toShape()
if round(pseudoarc.Length,Draft.precision()) != round(edge.Length,Draft.precision()):
ang1, ang2 = ang2, ang1
# method 2 - check the midpoint - not reliable either
#ve3 = DraftGeomUtils.findMidpoint(edge)
#ang3 = -math.degrees(DraftVecUtils.angle(ve3.sub(ce)))
#print ("edge ",edge.hashCode()," data ",ang1, " , ",ang2," , ", ang3)
#if (ang3 < ang1) and (ang2 < ang3):
# print ("inverting, case1")
# ang1, ang2 = ang2, ang1
#elif (ang3 > ang1) and (ang3 > ang2):
# print ("inverting, case2")
# ang1, ang2 = ang2, ang1
#elif (ang3 < ang1) and (ang3 < ang2):
# print ("inverting, case3")
# ang1, ang2 = ang2, ang1
return DraftVecUtils.tup(ce), radius, ang1, ang2
if round(edge.Curve.Axis.dot(FreeCAD.Vector(0,0,1))) == 1:
ang1,ang2=edge.ParameterRange
else:
ang2,ang1=edge.ParameterRange
return DraftVecUtils.tup(ce), radius, math.degrees(ang1),\
math.degrees(ang2)
def getSplineSegs(edge):
"returns an array of vectors from a Spline or Bezier edge"
@ -1429,34 +1395,13 @@ def getWire(wire,nospline=False,lw=True):
for edge in edges:
v1 = edge.Vertexes[0].Point
if DraftGeomUtils.geomType(edge) == "Circle":
mp = DraftGeomUtils.findMidpoint(edge)
v2 = edge.Vertexes[-1].Point
c = edge.Curve.Center
angle = abs(DraftVecUtils.angle(v1.sub(c),v2.sub(c)))
if DraftGeomUtils.isWideAngle(edge):
if angle < math.pi:
angle = math.pi*2 - angle
# if (DraftVecUtils.angle(v2.sub(c)) < DraftVecUtils.angle(v1.sub(c))):
# angle = -angle
# polyline bulge -> negative makes the arc go clockwise
angle = edge.LastParameter-edge.FirstParameter
bul = math.tan(angle/4)
# OBSOLETE because arcs can have wrong normal
# the next bit of code is for finding the direction of the arc
# a negative cross product means the arc is clockwise
#tang1 = edge.Curve.tangent(edge.ParameterRange[0])
#tang2 = edge.Curve.tangent(edge.ParameterRange[1])
#cross1 = Vector.cross(Vector(tang1[0][0],tang1[0][1],tang1[0][2]),Vector(tang2[0][0],tang2[0][1],tang2[0][2]))
#if DraftVecUtils.isNull(cross1):
# special case, both tangents are opposite, unable to take their cross vector
# we try again with an arbitrary point at a third of the arc length
#tang2 = edge.Curve.tangent(edge.ParameterRange[0]+(edge.ParameterRange[1]-edge.ParameterRange[0]/3))
#cross1 = Vector.cross(Vector(tang1[0][0],tang1[0][1],tang1[0][2]),Vector(tang2[0][0],tang2[0][1],tang2[0][2]))
#if cross1[2] < 0:
# polyline bulge -> negative makes the arc go clockwise
#bul = -bul
if not DraftGeomUtils.isClockwise(edge):
if edge.Curve.Axis.dot(FreeCAD.Vector(0,0,1)) < 0:
bul = -bul
points.append(fmt(v1,bul))
elif (DraftGeomUtils.geomType(edge) in ["BSplineCurve","BezierCurve","Ellipse"]) and (not nospline):